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Re: No results from the sgx_emmt tool.

Li__Xiaoguo
Beginner
1,166 Views

Hi,

I also encounter the same problem in Ubuntu 18.08 after enabling sgx_emmt when I use the sgx-gdb for debugging my program.

It prints the stack used normally. However, the heap used cannot print normally. Please refer to the following output.  

--------output---------------

[Peak stack used]: 7 KB
[Can't get peak heap used]: You may use version script to control symbol export. Please export 'g_peak_heap_used' in your version script.
[Can't get peak committed reserved memory]: You may use version script to control symbol export. Please export 'g_peak_rsrv_mem_committed' in your version script.

-----------output ---------------

Should I modify the python script ( sgx_emmt.py )?

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1 Solution
JesusG_Intel
Moderator
1,138 Views

Hello Li_Xiaoguo,


According to the section Enclave Memory Measurement Tool of the Intel SGX Developer Reference Guide for Linux, you must export g_peak_heap_used and g_peak_rsrv_mem_committed in the version script of the enclave.


In the SGX SDK sample, SampleEnclave, the enclave version script is /SampleEnclave/Enclave/Enclave.lds and its content is:


enclave.so

{

  global:

    g_global_data_sim;

    g_global_data;

    enclave_entry;

    g_peak_heap_used;

    g_peak_rsrv_mem_committed;

  local:

    *;

};


The Makefile must reference the version scrypt and define the symbol __ImageBase, similar to:

$ ld -o enclave.so file1.o file2.o \

-pie -eenclave_entry -nostdlib -nodefaultlibs –nostartfiles --no-undefined \

--whole-archive –lsgx_trts --no-whole-archive \

--start-group –lsgx_tstdc ––lsgx_tservice -lsgx_crypto -

-end-group \

-Bstatic -Bsymbolic --defsym=__ImageBase=0 --exportdynamic \

--version-script=enclave.lds


The SampleEnclave provided in the SGX SDK already has all of this in place so you can reuse its Makefile and version script.


Sincerely,

Jesus G.

Intel Customer Support


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2 Replies
JesusG_Intel
Moderator
1,139 Views

Hello Li_Xiaoguo,


According to the section Enclave Memory Measurement Tool of the Intel SGX Developer Reference Guide for Linux, you must export g_peak_heap_used and g_peak_rsrv_mem_committed in the version script of the enclave.


In the SGX SDK sample, SampleEnclave, the enclave version script is /SampleEnclave/Enclave/Enclave.lds and its content is:


enclave.so

{

  global:

    g_global_data_sim;

    g_global_data;

    enclave_entry;

    g_peak_heap_used;

    g_peak_rsrv_mem_committed;

  local:

    *;

};


The Makefile must reference the version scrypt and define the symbol __ImageBase, similar to:

$ ld -o enclave.so file1.o file2.o \

-pie -eenclave_entry -nostdlib -nodefaultlibs –nostartfiles --no-undefined \

--whole-archive –lsgx_trts --no-whole-archive \

--start-group –lsgx_tstdc ––lsgx_tservice -lsgx_crypto -

-end-group \

-Bstatic -Bsymbolic --defsym=__ImageBase=0 --exportdynamic \

--version-script=enclave.lds


The SampleEnclave provided in the SGX SDK already has all of this in place so you can reuse its Makefile and version script.


Sincerely,

Jesus G.

Intel Customer Support


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JesusG_Intel
Moderator
1,116 Views

This thread has been marked as answered and Intel will no longer monitor this thread. If you want a response from Intel in a follow-up question, please open a new thread.


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